One of the primary applications of plastics materials is food packaging where permeability to gasses such as oxygen is not desired. Oxygen and water are well know chemical reagents for reactions with food and other sensitive substrates. This severely reduces the packed materials service life. Polymer material ranging from polyesters based upon monomers such as terephthalic acid copolymerized with alkane diols to copolymers of ethylene and vinyl alcohol have been used as high oxygen (and other gas) barrier materials. Other polymers such as nylon, polyvinylidene dichloride, nylon and copolymers of maleic anhydride and acrylic acid also function as polymeric gas barrier materials. Uses of gas barrier films include packaging of food and liquids, electronics, pharmaceuticals, and chemicals. In general polymeric packaging materials are fabricated by processing polymeric materials into sheets or thin films, laminated of multiple pre-formed thin polymer films, injection molding, blow molding, compression molding, and other processes which require elevating preformed polymers to high temperatures followed by a cooling or series of cooling cycles. Alternatively, thermally cured coatings with barrier properties may be used to coat low barrier polymers.
Traditional coatings or films used to improve gas barrier on applied substrates involves long application and processing times often at high temperatures, thermoforming requiring expensive equipment, use of environmentally unfriendly solvents, and the problems caused by shrinking during the above processing steps. A successful UV cured coating that significantly improves the barrier resistance of substrate materials could reduce processing costs and processing times.